Figure 3A showed the overall distribution of ACE2+ cells in different subsets. The frequency of ACE2+ cells increased significantly in three of four CMs subsets in HF patients, especially in CM1(p < 0.0001) and CM4 (p < 0.0001), while its frequency in CM2 subset did not change significantly (p > 0.05; Figure 3B). Moreover, the percentages of ACE2+ cells in fibroblasts (p < 0.0001) and smooth muscle cells (p = 0.0104) were both significantly decreased. The frequency of ACE2+ cells in NK-T Cell/Monocytes and granulocytes was insignificantly changed (p > 0.05; Supplementary Table 2). Here, ACE2 is linked to hydrops fetalis.